WASHINGTON — The number of women in Congress is likely to reach record highs after the Nov. 8 election, boosting female lawmakers to more than 20% of the House and Senate for the first time while also reflecting the continued difficulty of achieving equal representation.

The new record will be set despite the fact that Election Day results are likely to produce only modest increases in the overall numbers of women in Congress, reflecting slow change in the legislative branch at a time when the nation may be poised to elect its first female president.

"I think it's misleading if, after the election, we have a big, screaming headline that says 'record number of women in House and Senate’ when women are still less than 25% of Congress,” said Debbie Walsh, director of the Center for American Women and Politics at Rutgers University's Eagleton Institute of Politics. “The small increases we’re expecting are nothing to dance in the streets about."

Projections by the center show that the number of women in the 100-member Senate could rise from 20 to as high as 23 despite the retirement of two veteran Democratic women: Sens. Barbara Boxer of California, who has served for 24 years, and Barbara Mikulski of Maryland, who has served 30 years in the Senate and 10 in the House, making her the longest-serving woman in the history of Congress.

Two states have Senate races where both candidates are women. In New Hampshire, Republican Sen. Kelly Ayotte is facing a strong challenge from Democratic Gov. Maggie Hassan. In California, two Democratic women — Rep. Loretta Sanchez and state Attorney General Kamala Harris — are vying to replace Boxer.

In the 435-member House, the number of female members could increase by about a dozen, boosting the total from 84 to 96, according to an analysis by Kelly Dittmar, an assistant professor of political science and a scholar at the center.

A 2017 freshman class of a dozen women in the House would be just half of what it was in 1992, when 24 new women were elected in what was dubbed the "Year of the Woman." Still, it would be the fourth-largest female freshman class since 1976.

Dittmar, using recent ratings data from the non-partisan Cook Political Report, said the number of Republican women in the House "will almost certainly decline" due to retirements and defeats in the primary election contests. In contrast, she said, Democrats have many more female candidates heading into the Nov. 8 election.

EMILY's List, which supports Democratic women who favor abortion rights, and has become the most powerful single group in the nation for electing women to office, is backing nine female Senate candidates and 33 female House candidates in this year's election.

Women already make up nearly a third of Democratic senators and more than a third of Democratic House members. After this election, their clout in the Democratic caucus should be even greater, said Stephanie Schriock, president of EMILY's List.

"For us, it has been years and years in the making to get to this point," said Schriock, noting that there were no Democratic women in the Senate in 1985 when the group was founded and only 11 Democratic women in the House.

Walsh said both political parties need to do more to recruit women candidates to run for Congress.

"When women run, they win at about the same rate as men," she said.

But women are less likely to be asked to run, Walsh said.

"The recruiters by and large are still men, and they tend to pick men who look like them," she said.

This year, 272 women filed to run for the House, which was down from the 2012 record of 298 women. Of those candidates, 167 women — 120 Democrats and 47 Republicans — won their primaries, barely more than the 2012 record of 166, according to Dittmar's research.

In the Senate, a record 40 women filed to run. Of those, 15 women — 11 Democrats and four Republicans — survived their primaries to become their party's nominee. That was down from 18 women nominees in 2012.

Another obstacle in recruiting women is that they tend to be the primary caregivers for children, Schriock said.

"Concerns about family and children are always a big part of the conversation," she said. "They'll ask: how am I going to manage this? What happens when I win?"

House Minority Leader Nancy Pelosi, D-Calif., the only woman ever to serve as speaker of the House, waited until the youngest of her five children was a senior in high school before running for Congress at the age of 47. Many women make that same choice, meaning they are often older than men when they run for elected office for the first time and have shorter political careers as a result, Walsh said.

Schriock said she hopes that will change with role models such as Sen. Kirsten Gillibrand, D-N.Y., who gave birth to her second son while serving in the House and went on to win election to the Senate. On the Republican side, Rep. Cathy McMorris Rodgers of Washington has given birth to three children while serving in Congress. She is chairwoman of the House Republican Conference, making her the highest-ranking Republican woman in the House.

"One of the reasons I'm so encouraging of women in their 20s to run for office is that they get in and realize that they can still have their families while they're serving," Schriock said. "It's a little less daunting if you're already in."